vector is loosing mat4 information

Question

I have a List of Entities I want to update and than render. For updating:

Variable:

std::vector<Entity> entityList;

function:

void EntityController::update(){
    for(Entity e : entityList){        
        e.update();
    }
}

and the update function for the entity

void Entity::update(){

glm::mat4 trans = glm::mat4();
trans = glm::translate(trans, glm::vec3(50.0f,0.0f,50.0f));
trans = glm::scale(trans, glm::vec3(21.0,21.0,21.0));

modelMatrix = trans;
}

My problem here is, that the model matrix actually works. I can find all my information when I take a look at it (Debugging mode XCode), as long as I am in the class entity.

But When I am out of that class, the information in the model matrix is the identity matrix again. somehow he does not save, or update the information :S

The most likely cause is that you are modifying a copy, not the original object. — R Sahu, Nov 23 '15 at 18:32
That's my guess. It will be better if you can post a [Minimal, Complete, and Verifiable example](http://stackoverflow.com/help/mcve). — R Sahu, Nov 23 '15 at 18:36
I added a little bit in the code. somehow I forgot the for each loop. But I don't know what information more could be necessary. — DomiDiDongo, Nov 23 '15 at 18:47

genpfault · Accepted Answer · 2015-11-23T18:54:27.613

2

You're update()ing Entity copies with your current range for:

for(Entity e : entityList)
          ^ huh?

You probably wanted references:

for(Entity& e : entityList)
          ^ important

edited Nov 23 '15 at 18:54

answered Nov 23 '15 at 18:48

genpfault

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thank you, didn't know that :S – DomiDiDongo Nov 23 '15 at 18:57

vector is loosing mat4 information

1 Answers1